Educational information, not medical advice — ask your doctor or midwife.
Track Flotation REST (Tank) with reminders and record whether it helped, in the app.
Flotation REST (Restricted Environmental Stimulation Therapy) involves lying in a lightproof, soundproof pod or room filled with about 10 inches of water saturated with roughly 800–1,000 lbs of Epsom salt, making your body float on the surface without any effort. The water is kept at skin temperature (around 93.5°F / 34.2°C) so you gradually lose the sense of where your body ends and the water begins. The result is a state of profound physical and mental stillness that's genuinely difficult to achieve through other means.
By removing almost all sensory signals — gravity, light, sound, and temperature contrast — your nervous system shifts from its usual high-alert state into deep parasympathetic rest. Your brain naturally drifts into theta brainwaves (the same state experienced in the moments just before sleep), your stress hormones drop, and your muscles release tension they've been holding without you even knowing. At the same time, the high magnesium content of the water may be absorbed through the skin, supporting muscle relaxation and nervous system calm.
Most people experience flotation at a dedicated float center in a pod (enclosed, egg-shaped) or a float room (a walk-in cabin with more space). Home tanks are available for purchase and are popular with serious practitioners. Sessions typically run 60–90 minutes, with some centers offering 2-hour or longer options. Open float pools exist but are less common and provide less complete sensory isolation.
Flotation REST was developed in the 1950s by American neuroscientist John C. Lilly, who was studying the effects of sensory deprivation on consciousness. By the 1970s–80s, researchers including Peter Suedfeld and Roderick Borrie began investigating its therapeutic applications, and clinical research has expanded significantly since the 2010s with formal trials on anxiety, pain, and athletic performance.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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